Hotfix: Fix closing dropdowns

This fixes a bug with the event binding for the close elem. The
function name was updated to use our private function name
scheme but the event binding was still using the old name. This
was causing errors when clicking the close button on a dropdown.

assets/js/romo/dropdown.js

@@ -284,7 +284,7 @@ RomoDropdown.prototype._bindBody = function() {
 
   this.closeElem = Romo.find(this.popupElem, '[data-romo-dropdown-close="true"]')[0];
   if (this.closeElem !== undefined) {
-    Romo.on(this.closeElem, 'click', Romo.proxy(this.onPopupClose, this));
+    Romo.on(this.closeElem, 'click', Romo.proxy(this._onPopupClose, this));
   }
 
   Romo.setStyle(this.contentElem, 'min-height', Romo.data(this.elem, 'romo-dropdown-min-height'));